Benzyl (2-{[(4-{(3S)-3-[(tert-butoxycarbonyl)amino]piperidin-1-yl}pyridin-3-yl)amino]carbonyl}-7-formylquinolin-3-yl)carbamate (0.008 g, 0.01 mmol) (from Example 15, step 5) was mixed with pyrrolidine, DCM (0.20 mL) and sodium triacetoxyborohydride (0.020 g, 0.094 mmol). The reaction mixture was stirred at room temperature for 2 h. HBr in AcOH (8.0 M; 0.20 mL, 1.6 mmol) was added and the reaction mixture was stirred at room temperature for 30 min. After concentration to remove the solvent, the crude product was diluted with MeOH and neutralized with a small amount of NH4OH. The mixture was filtered and purified by preparative LC-MS (pH=10 method; XBridge™ preparative C18 5 μm OBD™ column, 30×10 mm, 60 mL/min., eluting with a gradient of MeCN and water with NH4OH) to give the title compound. LCMS calc. for C25H32N7O (M+H)+: m/z=446.2. Found: 446.1.
